A prior art assembled opener with an illumination device is shown in FIG. 7. The primary structure thereof includes a handle a, a linkage portion b, and a tool portion c. The tool portion c may be a flat head opener, a cruciform opener, or a hexagonal opener, for example. An embedding head is installed in front of the handle a, which serves to directly or indirectly be combined with the tail portion of the linkage portion b. Another embedded head at the other end of the linkage portion b is for combining with the tool portion c. Therefore, a practical manual tool is formed.
The linkage portion is a hollow cylinder, and the rear end thereof is installed with a lamp set d. The front end of the lamp set d has a light guide structure e. The light guide structure has a defect in that due to the construction of the linkage portion b, while light within the linkage portion b transmits to the tool portion c from the light guide structure e (or a trench in the lateral side), a part of the light will be blocked by the tool portion c, and thus a shadow is formed. This is a defect in need of improvement.